This is the very reason I have fallen in love with Pathfinder and its creator's. The communication, the development of game aids, and the friendliness and willingness of everyone to talk and discuss. It's one of the reasons that I bought the "Book of the River Kingdoms". A big thank you to Dale for putting this on his website and helping the creator of the spreadsheet to make it better.

Anyway, I have a weird question, please keep in mind that I'm a new GM and all, but how many districts can be fit in 1 hex?

It's just curiosity, and I doubt my players will try to fill it up, but unless my math is wrong a hex is about 93 square miles, and if each district is about 1 square mile does that mean that, technically, we should be able to fit 90+ disctricts into it?

This has been figured before...

The short answer is:
A hex is approximately 125 square miles in size.
A city district is 1 square mile (1 mile per side)

I started working on it last night. One thing I have noticed right away is that it mass represents things. You can't have a mountain in just part of a hex, it is either the whole hex or not at all. Also, rivers are along the edge of the hexes, so you need to be a little liberal in your placement of them. I'll see if I can't post something by the end of the week.

b. claim hexes (My group claimed the Temple of the Elk hex, a forest hex, you can start elsewhere) -1BP, +1 Consumption

c. start a new city (Staghart was started, this will take two months before you can build because it was started in a forest hex. We will assign the bottom as water and the rest of the sides of the district as land.) +1 Consumption
d. build roads – none
e. designate farmlands – can not in forest’s or in hexes with cities
f. pick edicts – This is where I house ruled that once picked, festivals could not be changed for a year. Let’s start with basic edicts, Promotion: Token (+1 Stability, -1BP), Taxation: None (0 Economy, +1 Loyalty), and 1 Festival per year (+1 Loyalty, -1BP)

You are now at 47BP, having spent 3 during the Improvement Phase. Consumption is now at 2. Your Economy value is unchanged, Loyalty is up 2 to 17, and Stability is up 1 to 12)

Income Phase:
a. Deposit (You may have some items left over from adventuring, so lets say you have enough small items to deposit 4000gp worth.) Add +1BP.
b. Withdraw (Let’s assume for now you don’t need any cash)
c. Sell (You may have one or two items that you wish to sell, but you have not established your city district yet. So you can not sell at this time. You must wait until your city is established.)
d. Generate income (Here we can attempt to make some BP for your kingdom) My group rolled a 22 on their first attempt. This makes the Control DC of 21, and nets you 4BP.

You are now at 52BP, having gained 5 during the Income Phase.

Event Phase:
Your GM should roll a chance for an event. 25% chance at this point. Let’s assume you don’t get an event at this point.

Your first month as a new kingdom is finished. Congratulations!

Second MonthUpkeep Phase:
a. Stability check (This is still at 12 until you change things in future phases.) My group made their first check, so let’s assume you do as well. The DC for this is currently 21 (20 + 1 for kingdom size, one hex claimed). Since you don’t have any unrest to begin with, you gain 1BP.
b. Consumption (You consumption is currently 2, 1 for one hex, and 1 for a city district.) -2BP
c. Magic Items (You do not have a building to create magic items, yet.)
d. Unrest (You are at 0, nothing to worry about.)

You are now at 51BP, having spent 2 for consumption and gained 1 from stability.

Improvement Phase:
a. Assign leadership (Let’s just keep them the same.)
b. Claim hexes (Let’s claim the forest hex directly east so we can make a b-line for the grassland and start farming.) -1BP, +1 Consumption
c. City Improvements (We still need to wait a month before we can begin building in this city. I did hand waive this for my group, so that they could start building right away.)
d. Build roads (We have a new hex, let’s build a road in it. I ruled that if a city is built in a hex, so is a road.) Forest road -2BP, needs a bridge -2BP.
e. farmland (still unable to do this, since you have no grassland or hill hexes)
f. Edicts (Let’s keep them the same for now.)

You are now at 46BP, having spent 5 during this phase. You have also increased consumption by 1 to 3BP per turn.

Income Phase:
a. Deposit (Let’s assume you already deposited everything you could last time.)
b. Withdraw (Not yet)
c. Sell (Nothing yet)
d. Generate Income – Let’s assume you get a bad roll this time, 18, this gets you nothing.

You are now at 46BP, having neither gained nor spent BP.

Event Phase:
You GM should roll for a chance at an event. 50% chance at this point. Let’s assume you still don’t get an event.

Your second month is over, the next month you can begin construction of a building and possibly even establish some farmland.

Third MonthUpkeep Phase:
a. Stability check (This is still at 12 until you change things in future phases.) My group made their second check, so let’s assume you do as well. The DC for this is currently 22 (20 + 2 for kingdom size, two hexes claimed). Since you don’t have any unrest to begin with, you gain 1BP.
b. Consumption (You consumption is currently 3, 2 for two hexes claimed, and 1 for a city district.) -3BP
c. Magic Items (You do not have a building to create magic items, yet.)
d. Unrest (You are at 0, nothing to worry about.)

You are now at 44BP, having spent 3 for consumption and gained 1 for stability.

Improvement Phase:
a. Assign leadership (Let’s just keep them the same.)
b. Claim hexes (Let’s claim the hill hex directly east so we can start farming.) -1BP, +1 Consumption
c. City Improvements (We can now build, let’s start with a Temple since you have a ruined temple already it will only cost half price.) -16BP, 2 minor item slots, +2 Stability, +2 Loyalty, -2 Unrest
d. Build roads (We have a new hex, let’s build a road in it. I ruled that if a city is built in a hex, so is a road.) Hill road -1BP.
e. farmland (All right, we now have a hill hex, let’s establish farmland.) -4BP, -2 Consumption
f. Edicts (Let’s keep them the same for now.)

You are now at 24BP, having spent 22 during this phase. You have also decreased consumption by 1 to 2BP per turn. (3 for hexes claimed, 1 for city district, -2 for farmland) Stability has increased to 14 and Loyalty has increased to 19.

Income Phase:
a. Deposit (Let’s assume you already deposited everything you could last time.)
b. Withdraw (Not yet)
c. Sell (Nothing yet)
d. Generate Income – Let’s assume you get a great roll this time, 30, this gets you 6BP.

You are now at 30BP, having gained 6 from income.

Event Phase:
You GM should roll for a chance at an event. 75% chance at this point. Let’s assume you get an event. Roll random percent to see what you get. My group got an Outstanding Success on their first roll. This gives them +1d6 BP, +4 bonus to Economy checks until the next event phase, and -2 Unrest.

You are now at 34BP, having gained 4 from an Event.

Fourth Month
I figured I better do the fourth month, so that I can add in the magic item creation and selling.
Upkeep Phase:
a. Stability check (This is now at 14, thanks to building the temple.) My group made their third check, so let’s assume you do as well. The DC for this is currently 23 (20 + 3 for kingdom size, three hexes claimed). Since you don’t have any unrest to begin with, you gain 1BP.
b. Consumption (You consumption is currently 2, 3 for three hexes claimed, 1 for a city district, -2 for farmlands.) -2BP
c. Magic Items (You can now create magic items.) Roll randomly, we use the tables in the Core Rulebook and Gamemastery Guide. Let’s assume you gain one minor item worth less than 4,000gp and one minor item worth more than 4,000gp.
d. Unrest (You are at 0, nothing to worry about.)

You are now at 33BP, having spent 2 for consumption and gained 1 for stability.

Improvement Phase:
a. Assign leadership (Let’s just keep them the same.)
b. Claim hexes (Let’s claim the grassland hex directly north so we can continue farming and quickly incorporate Oleg’s.) -1BP, +1 Consumption
c. City Improvements (We built a temple last time, so lets build something to increase Economy this time. How about a graveyard? The cost is halved because we have a Temple, and we get an Economy bonus.) -2BP, +1 Economy, +1 Loyalty
d. Build roads (We have a new hex, let’s build a road in it. I ruled that if a city is built in a hex, so is a road.) Grassland road -1BP.
e. farmland (All right, we now have a grassland hex, let’s establish farmland.) -2BP, -2 Consumption
f. Edicts (Let’s keep them the same for now.)

You are now at 18BP, having spent 6 during this phase. You have also decreased consumption by 1 to 1BP per turn. (4 for hexes claimed, 1 for city district, -4 for farmland) Economy has increased to 16 and Loyalty has increased to 20.

Income Phase:
a. Deposit (Let’s assume you already deposited everything you could last time.)
b. Withdraw (Not yet)
c. Sell (We now have something to sell.) We only have one city district so we can only attempt to sell one item. We are going to attempt to sell the item worth more than 4,000gp. The DC for this roll is 20 for a minor item. Since you have a +4 bonus to this check, it’s a no brainer. You roll an Economy check and easily get it. +2BP
d. Generate Income – Let’s assume you get an average roll this time, 30 (+16 normally, +4 bonus = +20 to the roll), this gets you 6BP.

You are now at 26BP, having gained 8 from sales and income.

Event Phase:
You GM should roll for a chance at an event. Since you had an event the last time your chance drops back down to 25%. Let’s assume you get an event. Roll random percent to see what you get. You got lucky and got an Economic boon. This gives you +1d6 BP.

You are now at 34BP, having gained 8 from an Event. (You get to reroll 6’s and keep adding the results.)